• Analytical Science and Technology
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• v.19 no.6
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• pp.535-543
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• 2006

Being used widely in semiconductor and display manufacturing, $NF_3$ is internationally considered as one of the regulated compounds in emission. Numerous companies have been continuously trying to reduce the emissions of $NF_3$ to comply with the global environmental regulation. This work is made to report the destruction and removal efficiency (DRE) of electrically heated scrubbers and the use rate in process chambers installed in three main LCD manufacturing companies in Korea. As the measurement techniques for $NF_3$ emission, mass flow controlled helium gas was continuously supplied into the equipment by which scrubber efficiency is being measured. The partial pressures of $NF_3$ and helium were accurately measured for each sample using a mass spectrometer, as it is emitted from inlet and outlet of the scrubber system. The results show that the DRE value for electrically heated scrubbers installed before 2004 is less than 52 %, while that for the new scrubbers modified based on measurement by scrubber manufacturer has been sigificentely improved upto more than 95 %. In additon, we have confirmed the efficiency depends on such variables as the inlet gas flow rate, water content, heater temperature, and preventative management period. The use rates of $NF_3$ in process chambers were also affected by the process type. The use rate of radio frequency source chambers, built in the $1^{st}$ and $2^{nd}$ generation process lines, was determined to be less than 75 %. In addition, that of remote plasma source chambers for the $3^{rd}$ generation was measured to be aboove 95 %. Therefore, the combined application of improved scrubber and the RPSC process chamber to the semiconductor and display process can reduce $NF_3$ emmision by 99.95 %. It is optimistic that the mission for the reduction of greenhouse gas emission can be realized in these LCD manufacturing companies in Korea.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.77-83
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• 2009

This study was conducted to investigate the chemical composition and biological function of tea made from mountain-cultivated ginseng leaves. The antioxidant activities of tea made from mountain-cultivated ginseng leaves were determined by measuring their electron-donating ability based on their DPPH and nitrite-scavenging ability. The electron-donating abilities of tea made from mountain-cultivated ginseng leaves (500 and 1,000 ppm) as determined by DPPH assay were 45.6 and 85.1%, respectively. The nitrite scavenging ability of tea made from mountain-cultivated ginseng leaves (500 and 1,000 ppm) at pH 6.0 were 32.8 and 51.4%, respectively. Furthermore, the nitrite scavenging activity increased in a dose-dependent manner at all pH values. The effects of tea made from mountain-cultivated ginseng leaves on Male Sprague-Dawley rats were also evaluated. To accomplish this, the rats were divided into three groups (A: normal diet group, B: high fat diet group and C: high fat diet supplemented with tea made from mountain-cultivated ginseng leaves group). The anti-obesity effects of tea made from mountain-cultivated ginseng leaves were then evaluated. The serum total lipid, total cholesterol and triglyceride contents in C group were lower than those of B group; however, these differences were not statistically significant. The HDL-cholesterol content was significantly higher in the C group than in the other groups. Taken together the results of this study suggest that tea made from mountain-cultivated ginseng leaves possesses antioxidant activity and improves lipid metabolism.

• Journal of Korea Entertainment Industry Association
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• v.13 no.7
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• pp.361-373
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• 2019

Falls are a threat to the physical health of the elderly as well as to their overall quality of life. The purpose of this study was to identify which type of exercise is effective for improving the balance of the elderly, and to obtain the basic data for developing the falls prevention exercise intervention program for the elderly. We compared to the differential effects between rhythmic step exercise and core muscle strengthening exercise in terms of functional balance test and self-reported balance test. Women older than 65 years and under 80 years of age were assigned to one of the step exercise group(21), core muscle exercise group(20), and control group(21), and for 8 weeks, twice per week, 20-30 minutes of exercise were treated. All participants performed one foot static balance test with open and closed eyes. And they responded to self-reported balance test, such as Fall Efficacy Scale(FES) and Activities-specific Balance Confidence(ABC) Scale. The results of statistical analysis are summarized as follows. First, rhythmic stepping exercise was more effective in improving functional balance than core muscle strengthening exercise. In particular, the effect of step exercise was obvious in the one-foot static balance test with open eyes. Second, the self-reported balance test showed better step exercise than core muscle exercise. Specifically, rhythmic step exercise was more effective in enhancing fall efficacy than core muscle exercise. In conclusion, the rhythmic step exercise was more effective in improving the balance ability of the elderly than the core muscle exercise. The rhythmic step exercise is more related to the lower extremity muscles, and especially since the rhythmic step exercise is performed in various ground changes, it seems to have a high similarity to the fall occurrence situation. For future research, we recommended the development of task-oriented ankle proprioceptive exercise intervention program and exercise equipment based on the specific motion situation in which the fall accident occurs in the elderly.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.103-103
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• 2022

다복찰은 전라북도농업 기술원에서 2012~2020년에 신명흑찰과 익산488호를 교배하여 육성한 찰벼이며, 중대립, 단간, 내도복, 다수성의 특징을 보인다. 동진찰은 1998년도에 육성되었으며, 우리나라에서 가장 인기 있는 찰벼이다(재배면적 25,161ha/2021년 기준). 드문모심기 재배 기술은 2017년부터 도입되었으며, 밀파 육묘하여 재식밀도 및 재식주수를 감소함으로써 소요되는 재료비 등 경비 및 투입되는 노동력을 절감하는 경제성 있는 기술이다. 따라서 본 연구는 전라북도농업기술원에서 육성한 다복찰 보급 확대 및 가장 인기 높은 동진찰의 드문모심기 재배기술 확립 일환으로 시작되었으며, 2024년까지 3년간 실시할 계획이다. 시험은 기술원 논 포장에서 실시하였으며, 시험품종은 다복찰, 동진찰, 시험요인은 이앙시기(3처리) 및 재식밀도(4처리)를 두었다. 이앙시기별로 이앙 17일 전에 온탕소독(62℃, 10분), 종자소독(32℃, 1일), 침종(32℃, 1일), 간이출하(30℃, 3일) 과정을 거쳐 부직포 육묘(12일 정도)를 실시하였다. 5월20일(이앙520)부터 5월30일(이앙530), 6월9일(이앙609)까지 10일 간격으로 드문모심기 전용 이앙기로 이앙하였으며, 주당 본수는 5.7개 정도였다. 이앙 시기별로 시험포장을 구분하였고 포장내에 2품종, 각각 3.3m2당 80주, 60주, 50주, 37주 등 재식밀도 처리구를 두었으며, 처리구마다 3반복 조사구(10주/반복, 5본/주) 설치하였다. 10a당 9-4.5-5.7kg(N-P₂O₅-K₂O)를 밑거름(50%)-분얼거름(20)-이삭거름(30) 등 3회 거쳐 시비하였다. 중간물떼기는 이앙32일째부터 10일간 실시하였으며, 예상 출수 30일 전에 충분하게 담수하였다. 이앙20일째부터 10일 간격으로 경수, 초장, 엽색도 등 생육 조사, 그리고 출수기, 후기 생육 및 병해충을 조사하였다. 향후 수확기에 수량, 수량구성요소, 미질 및 품위를 분석할 계획이다. 시험토양은 pH 6.0~6.3, EC는0.68~0.85dS/m, 유기물함량은 52~57g/kg 수준으로 높았다. 동진찰 발아율(94.0~98.1%)이 다복찰(89.9~94.9%)보다 우수하였다(3~6%P ↑). 다복찰 묘 충실도(102~106mg/주)가 동진찰(79~101mg/주)보다 다소 좋았으며, 이앙530 묘소질이 가장 좋았다. 동진찰 초장은 다복찰에 비해 다소 길었으나 이앙시기 및 재식밀도별 초장의 변화 유형은 비슷하였다. 이앙520구의 80주에서 초장이 가장 작았고 이앙609구에서는 80주에서 다소 길었으나, 처리구간의 유의성은 없었다. 동진찰 및 다복찰 경수는 37주에서 이앙 후 40일째, 50주, 60주, 80주에서는 30일째 가장 컸다. 출수기는 다복찰에 비해 동진찰이 3~7일 정도 빨랐으며, 특히 이앙520 동진찰에서는 재식밀도가 높을수록 출수기가 빠른 경향을 보였으며, 이앙530 이후에는 재식밀도간 차이가 거의 없었다. 동진찰에 비해 다복찰 간장이 3~6cm 작았으며, 2품종 모두 이앙609구에서 가장 낮은 값을 보였다. 수장도 간장과 비슷한 경향을 보였다. 수수는 2품종 모두 이앙이 늦을수록 증가하였으며, 37주에서 가장 높았으며, 80주에 비해 다복찰, 동진찰 각각 73.8%, 77.4% 높았다. 다복찰의 경우 3.3m²당 수수는 이앙시기별과 관계없이 상대적으로 80주에서 가장 많았고 이앙520에서 재식밀도간 차이는 감소하였지만 이앙시기가 늦을수록 수수는 증가하는 경향을 보였다. 동진찰도 비슷한 경향을 보였으며, 이앙520과 이앙609 사이에 수수 차이는 적었다. 병 발생은 잎집무늬마름병, 세균성벼알마름병, 이삭누룩병이 주로 관찰되었으며, 세균성 벼알마름병은 출수기와 맞물린 이앙530에서 가장 크게 발생하였으며, 이앙520도 비슷한 경향을 보였다. 이삭누룩병 발생이 심하였는데 재식밀도간 차이보다는 이앙시기별 차이가 더 크게 발생하였으며 품종 간의 병 발생 차이는 없었다. 이상의 결과로 수수 측면에서 조기 이앙할 경우에는 50~60주, 늦은 이앙 시에는 80주가 유리할 것으로 보이며, 추후주당 립수, 등숙률, 천립중 등을 조사하고 경영비 등을 고려하여 합리적인 이앙시기 및 재식밀도를 판단할 수 있을 것으로 판단된다.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.683-701
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• 2023

Purpose: The purpose of the study was to analyze the status of dietary behavior and nutrition intakes according to the gender and the level of physical activity of adolescents. Methods: Data from 659 adolescents aged 13 to 18 years who participated in the Korea National Health and Nutrition Examination Survey (2017-2018) were analyzed. Collected data were analyzed using complex sampling data analysis with SPSS v. 27.0. Results: The adolescents were categorized into three groups based on their physical activity as follows: The first group with high physical activity (8.9%), a second group with normal physical activity (29.7%), and a third group without physical activity (61.4%). Boys showed significantly higher physical activity than the girls. Adolescents with high physical activity had a significantly lower body mass index than adolescents without physical activity, but their meal regularity, subjective health status, and recognition of body image were significantly higher. In terms of biochemical factors, adolescents with high physical activity had lower triglycerides and cholesterol than adolescents without physical activity, while hemoglobin and hematocrit were significantly higher. In addition, the intakes of energy, carbohydrates, proteins, fat, vitamin B₁, niacin, calcium, phosphorus, sodium, potassium, iron increased significantly as adolescents' physical activity increased. Conclusion: The physical activity of adolescents had a positive effect on dietary behavior, lifestyle, and nutritional factors. Therefore, it is necessary to increase participation in physical classes in schools and develop various programs considering the level of physical activity among adolescents.

• Journal of Forest and Environmental Science
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• v.3 no.1
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• pp.1-9
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• 1983

The purpose of this study was to elucidate the ecophysiological habitat of natural Sorbus commixta forest at Mt. Seorak. The results obtained were as follows: 1. The Sorbus commixta trees mainly distributed from 900m to 1,500m altitude. In there, the warm index(WI) was about 42$3.2{\times}10^3$ to $9.2{\times}10^3$, cation exchange capacity(CEC) was 13.7 to 19.5mg/100g, N content 0.21 to 0.39%, $P_2O_5$ content was 22.6 to 38.7ppm, and pH value was 5.6 to 5.8 respectively. 4. The upper crown trees in Sorbus commixta communities were Abies nephrolepis, Taxus cuspidata, Betula platyphylla var. japonica, Quercus${\times}$grosseserrata, Acer mono, Prunus sargentii, Carpinus cordata, Tilia amurensis, and the under crown trees were Rhododendron brachycarpum, Acer pseudo-sieboldianum, Thuja olientalis, Corylus heterohpylla, Philadelphus schrenckii, Rhododendron schlippenbachii, Rhododendron mucronulatum, and Magnolia sieboldii. 5. The stand densities were 1,156 trees/ha at 1,160m and 3,600 trees/ha at 1,300m respectively. The coverages by the DBH basal area were 0.37 at 1,160m and 0.31 at 1,300m respectively, and the vegetation coverages by the crown projection area were 2.04 at 1,160m and 1.61 at 1,300m respectively. 6. The light extinction coefficient(k) in Beer-Lambert's law, showed the distance, F(z), from top canopy to aboveground, was 0.17. 7. The water relations parameters of Sorbus commixta shoot were obtained by the pressure chamber technique. The osmotic pressure, ${\pi}_o$, at maximum turgor was -16.2 bar, and VAT pressure was 14.5bar. The osmotic pressure, ${\pi}_p$, at incipient plasmolysis was -19.4bar. The relative water contents at incipient plasmolysis were 83.1% ($v_p/v_o$) and 87.1%($v_p/w_s$;$w_s$, total water at maximum turgor). 8. The bulk modulus of elasticity(E) of shoot was about 69.6. The total symplasmic water to total water in shoot was 67.7%, and the apoplastic water to total water was 32.3%.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.133-141
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• 2016

The physicochemical properties, antioxidant capacities, and sensory optimization of taro (Colocasia esculenta) under different aging conditions were investigated to develop black taro. Black taro was processed in three steps (steaming: $95{\pm}3^{\circ}C$ for 1 h; aging: 85, 90, $95^{\circ}C$ for 20, 40, and 60 h; drying: $60^{\circ}C$ for 24 h) and ground into a powder for all experiments. Black taro showed an increased crude fiber content and browning index compared to raw taro. Calcium oxalate contents, reducing sugar contents, moisture contents, and lightness values were decreased during the processing of taro. Improvements in total polyphenol content and antioxidant activity (DPPH, ABTS, FRAP) were observed in the black taro samples aged at higher temperature. Response surface methodology was used for sensory optimization, and the optimum aging conditions with the highest acceptance values were found to be $88.73^{\circ}C$ for 39.50 h for taste, and $88.82^{\circ}C$ for 42.60 h for overall acceptance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.5 no.1
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• pp.69-86
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• 1969

On the growing of the interspecific hybrid ginseng plant, the phenomena of hybrid vigoures are observed in the root, stem, and leaf, but it can not produce seeds favorably since the ovary is abortive in most cases in interspecific hybrid plants. The present investigation was undertaken in an attempt to elucidate the embryological dses of the seed failure in the interspecific hybrid of ginseng (Panax Ginseng ${\times}$ P. Quinque folium). And the results obtained may be summarized as follows. 1). The vegetative growth of the interspecific hybrid ginseng plant is normal or rather vigorous, but the generative growth is extremely obstructed. 2). Even though the generative growth is interrupted the normal development of ovary tissue of flower can be shown until the stage prior to meiosis. 3). The division of the male gameto-genetic cell and the female gameto-genetic cell are exceedingly irregular and some of them are constricted prior to meiosis. 4). At meiosis in the microspore mother cell of the interspecific hybrid, abnormal division is observed in that the univalent chromosome and chromosome bridge occure. And in most cases, metaphasic configuration is principally presented as 23 II+2I, though rarely 22II+4I is also found. 5). Through the process of microspore and pollen formation of F1, the various developmental phases occur even in an anther loclus. 6). Macro, micro and empty pollen grains occur and the functional pollen is very rare. 7). After the megaspore mother cell stage, the rate of ovule development is, on the whole, delayed but the ovary wall enlargement is nearly normal. 8). Degenerating phenomena of ovules occur from the megaspore mother cell stage to 8-nucleate embryo sac stage, and their beginning time of constricting shape is variously different. 9). The megaspore arrangement in the parent is principally of the linear type, though rarely the intermediate type is also observed, whereas various types, viz, linear, intermediate, Tshape, and I shape can be observed in hybrid. 10). After meiosis, three or five megaspore are some times counted. 11). Charazal end megaspore is generally functional in the parents, whereas, in F1, very rarely one of the center megaspores (the second of the third megaspore) grows as an embryo sac mother cell. 12). In accordance with the extent of irregularity or abnormality in meiosis, division of embryo sac nuclei and embryo sac formation cause more nucellus tissue to remain within th, embryo sac. 13). Even if one reached the stage of embryo sac formation, the embryo sac nuclei are always precarious and they can not be disposed to theil proper, respective position. 14). Within the embryo sac, which is lacking the endospermcell, the 4-celled proembryo, linear arrangement, is observed. 15). Through the above respects, the cause of sterile or seed failure of interspecific hybrid would be presumably as follows, By interspecific crossing gene reassortments takes place and the gene system influences the metabolism by the interference of certain enzyme as media. In the F1 plant, the quantity and quality of chemicals produced by the enzyme system and reaction system are entirely different from the case of the parents. Generally, in order to grow, form, and develop naw parts it is necessary to change the materials and energy with reasonable balance, whereas in the F1 plant the metabolic process becomes abnormal or irregular because of the breakdown of the balancing. Thus the changing of the gene-reaction system causes the alteration of the environmental condition of the gameto-genetic cells in the anther and ovule; the produced chemicals cause changes of oxidatio-reduction potential, PH value, protein denaturation and the polarity, etc. Then, the abnormal tissue growing in the ovule and emdryo sac, inhibition of normal development and storage of some chemicals, especially inhibitor, finally lead to sterility or seed failure. Inconclusion, we may presume that the first cause of sterile or seed abortion in interspecific hybrids is the gene reassortment, and the second is the irregularity of the metabolic system, storage of chemicals, especially inhibitor, the growth of abnormal tissue and the change of the polarity etc, and they finally lead to sexual defect, sterility and seed failure.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.371-384
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• 1982

Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.

• Korean Journal of Animal Reproduction
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• v.22 no.4
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• pp.425-435
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• 1998

To improve the efficiency of nuclear transplantation in bovine, in this study the development in vitro of nuclear transferred (NT) embryos was compared by different activation regimens of the enucleated oocytes. The effect of developmental stage and culture system of donor nuclei on fusion and development in vitro of NT embryos were also evaluated. Oocytes were collected from Hanwoo ovaries obtained from slaughterhouse and matured in Ham's F-10 supplemented with hormones. After 20~22 h maturation, the oocytes were vortexed to be free from cumulus cells and subsequently their nucleus and the first polar body were removed. Enucleated oocytes were divided into 3 groups for activation; the oocytes of group I were activated with ionomycin for 5 min and subsequently incubated in 6-dimetylarninopurine (DMAP) for 4 h, Those of group II were treated with DMAP for 4 h at 39 h after onset of in vitro maturation (IVM) and those of group III were kept in room temperature ($25^{\circ}C$) for 3 h at 39 h after onset of IVM. After in vitro fertilization (IVF) the embryos for muclear donor were cultured either by group culture (20 embryos /50 ${mu}ell$ drop) or individually (1 embryo /50 ${mu}ell$ drop) for 4 day and 5 day. At day 4 and 5 after IVF, blastomeres were separated in calcium-magnesium free medium, and then classified into small (day 5: $\leq$ 38 ${\mu}{\textrm}{m}$, day 4: $\leq$ 46 ${\mu}{\textrm}{m}$) and large (day 5 : $\geq$ 38 ${\mu}{\textrm}{m}$, day 4 ; $\geq$ 46 ${\mu}{\textrm}{m}$). The separated blastomeres were replaced into enucleated and activated recipient cytoplasm. The blastomere-oocyte complexes were fused by electrically. The NT embryos were cultured in TCM-199 containing 10% FCS in 39$^{\circ}C$, 5% $CO_2$ incubator for 7 day. The results obtained were summarized as follows; There were no differences in fusion and development to blastocyst between groups as group I (68%, 10%), group II (75%, 14%) and group III (73%, 9%), respectively. However, the cell number in blastocyst of NT embryos in group III were significantly fewer than in the other groups (P＜0.05). No differences in fusion and development to blastocyst were found between individual or group cultured and between small or large blastomeres of day 4 and day 5 donor embryos. From these results, it was concluded that the combination of ionomycin and DMAP, or treatment of DMAP at 39 h after onset of IVM were useful for the efficient of production of NT bovine embryos, and the individual cultured embryos could be simply used as donor nuclei for NT bovine embryo.